Checkweighing scales are a key element of quality assurance in the manufacture of pharmaceuticals or cosmetics, food products and beverages, as well as in the logistics, chemical, automobile parts and metalworking industries. Checkweighing scales not only provide improved efficiency in the utilization of resources, but they also help in achieving conformance with national regulations, Weights and Measures requirements and industry standards. An effective checkweighing system provides protection against product defects and lowers overall operating costs.
A dynamic checkweighing scale is a system that measures the weights of objects in motion as they move over a scale in their path within a production line, wherein the weighed objects are classified according to specified weight brackets and are either sorted in accordance with their classification or taken out of the production line. Checkweighing scales are used in many different areas, including for example:                checking for underweight or overweight of products,        assuring compliance with legal requirements for the net contents of packaged goods,        reducing product give-away by adjusting the settings of the filling machines based on the weight data collected from the checkweighing scale,        measuring and recording the performance of the production facility or production line, and        verifying the piece count based on weight.        
With checkweighing scales, 100 percent of the articles in a production line are being weighed. Accordingly, complete production records are collected for product count, lot traceability, or production statistics.
A checkweighing system normally consists of an infeed conveyor, a weighing conveyor, an outfeed conveyor with sorting mechanism, and a weighing terminal with a user interface. The belt conveyor that lies between the infeed conveyor and the outfeed conveyor is normally mounted on a weighing cell which measures the weight of a product in motion as it travels over the weighing belt. The weighing technologies used most often for checkweighing scales are strain gauge load cells or weighing cells that function according to the principle of electromagnetic force compensation. After they have passed over the weighing conveyor, the products are transported away by an outfeed conveyor arranged downstream of the weighing conveyor. In the dynamic weighing process, products of non-conforming weight are detected and expelled by the sorting device, usually by a pusher element moving transverse to the transport direction of the products.
Next to checkweighing scales, metal detectors are likewise considered key components of an effective quality assurance program. Metal detectors are employed by industrial users for the detection of contaminants in products, for example lead pellets in meat, wire fragments in grain, splinters remaining from repair work in the production machinery, or other foreign matter that may be present in the product being processed.
An industrial metal detection system is a highly developed instrument with the ability to detect and sort out metallic foreign objects. Materials that are detectable include ferrous metals including stainless steels and non-ferrous metals such as brass, copper, aluminum and lead. A typical metal detection system consists of the following four main components: search head, transport system, user interface, and automatic sorter unit. The search head in most cases consists of a plurality of electromagnetic coils functioning, respectively, as senders and receivers of high-frequency electromagnetic fields.
An automated sorter unit has the task of segregating those products from the production stream which in a preceding product inspection have failed to meet the quality specifications set by the user. The segregation can be carried out in many different ways and also depends on the kind of product. Light-weight products such as for example edge-sealed bags can be removed from the product stream by a pulse blast from an air nozzle. In many more cases, however, the defective product is removed by a pusher unit which is operated mechanically by a pneumatic cylinder or by means of an electric motor.
The product that has been expelled from the original product stream either moves on to a further conveyor path and is thereby taken out of the product stream, or it is pushed into a holding bin directly next to the product stream. Accordingly, the holding bin is the place where all defective products of an inspection system are collected. The user of the inspection system now has the option to determine the nature of the product defects more closely by taking the respective articles out of the holding bin.
A holding bin for recyclable raw materials described in DE 3 333 316 A1 is shown with a tilting tub and a cover as a solution for improving the collection of recyclable raw materials. The tilting tub is set into the insertion guide near the bottom by means of two pivot pins that form an axis of rotation. Two pins form end stops that delimit the swivel movement of the tilting tub. This design of a container is not suitable for use as a holding bin in a sorter device, because the objects inside the container are removed through the same opening through which they entered the container. In addition, the container is not designed so that it could receive sorted-out articles at the same time as articles are taken out. In an automated production line with a sorter device, this capability is absolutely required, because otherwise the sorting would have to be interrupted.
A holding bin that is currently distributed by the applicant for installation in a sorting mechanism has an inlet opening at the height of the outfeed conveyor belt and a discharge device located closer to the ground. The discharge device is realized as a downward-tiltable flap which can take two positions: one position in which the holding container is closed and a second position in which the entire contents of the holding container can be dumped out. It has been found difficult to remove an individual sorted-out article, because when the flap is opened it swings out in the downward direction, allowing all of the articles inside to fall out.
It is therefore the object of this invention to provide a holding bin for a sorting device which is designed so that individual articles can be taken out of the bin easily, in particular by using preferably only one hand in the process.
It should further be possible that the sorting device does not need to be stopped while an article is taken out and that further articles that are to be sorted out can be moved into the holding bin at the same time.